Instructions for Otis King's Pocket Calculator


This 16-page pamphlet was printed on light green paper by Carbic Limited, the London manufacturer of the cylindrical slide rule invented by Otis King. It is titled: The Otis King Calculator: Instructions for Use. This form of pamphlet is typically found with King Calculators manufactured later than those that sold with Carbic's eight-page pamphlet. (See 1987.0788.06.) Thus, it was printed no earlier than the late 1960s. This pamphlet did, though, appear before the pound sterling was decimalized in 1971.

An introduction to the instrument has been added, and explanations have been expanded for multiplication and division, logarithms, and understanding the scales. The further examples are nearly identical to those in the earlier form of instructions. The explanations of how to use the logarithmic capabilities of Model L are the same except that the word "unity" has been replaced by the number 1. Discussions of compound roots and approximation have been added, and the explanation of finding the decimal point is expanded.

Reference: Dick Lyon, "Otis King's Patent Calculator,"

Date Made: ca 1965-1970

Maker: Carbic Limited

Location: Currently not on view

Place Made: United Kingdom: England, London

Subject: MathematicsRule, Calculating


See more items in: Medicine and Science: Mathematics, Science & Mathematics, Slide Rules


Exhibition Location:

Credit Line: Gift of John White

Data Source: National Museum of American History

Id Number: 1981.0922.11Accession Number: 1981.0922Catalog Number: 1981.0922.11

Object Name: pamphlet

Physical Description: paper (overall material)Measurements: overall: 20.5 cm x 12.8 cm; 8 1/16 in x 5 1/32 in


Record Id: nmah_904708

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